Protective chains

ABSTRACT

Chain comprising links connected together by resilient steel loops threaded through apertures in the links and with the ends of the loops closed by means of a locking member located on the ends of a loop when it is in a resiliently deformed condition such that the release of the loop after location of the locking member thereon causes interlocking between the locking member and the loop end.

United States atent 1191 Dohmeier Jan. 8, 1974 PROTECTIVE CHAINS 1,855,279 4/1932 Borg 152 239 [76] Inventor: Hans Otto Dohmeier, 24 Shipston FOREIGN PATENTS OR APPLICATIONS Johannesburg, South Africa 2,007,709 1/1970 France 152/243 [22] Filed Jan 19 1972 827,602 12/1951 Germany 152/239 PP 8,920 Primary ExaminerGerald M. Forlenza Assistant Examiner-Robert Saifer [30] Foreign Application Priority Data Atmmey Kenneth Madsen Jan. 28, 1971 South Africa 71/0553 [5 S T [52] U.S. Cl. 152/243 Chain comprising links connected t g ther by resilient [51] Int. Cl. B60c 27/00 Steel loops threaded through apertures in the links and [58] Field of Search 152/171, 239, 242, with the ends of the loops Closed y means of a lock- 152/243 ing member located on the ends of a loop when it is in a resiliently deformed condition such that the release [5 Ref ence i d of the loop after location of the lockingv member UNITED STATES PATENTS thereon causes interlocking between the locking memher and the loop end. 3,382,906 5/1968 Muller et al. 152/243 3,559,713- 2/1971 Mueller 152/243 9 Claims, 4 Drawing Figures PROTECTIVE CHAINS This invention relates to chains and more particularly but not exclusively to tire protective chains.

Tire protective chains find wide usage on earth moving machines where the chains not only protect the vehicle tires from heavy abrasive wear, but also against damage by cutting against sharp rock and other objects as well as providing good traction.

It is the object of the present invention to provide a chain and particularly tire protective chain which can be readily formed into designed patterns which can be easily repaired when broken and which may be'less expensively manufactured than presently available chains.

According to this invention there is provided a chain comprising links connected together by resilient steel loops threaded through apertures in the links and with the ends of the loops closed by means of a locking member located on the ends of a loop when it is in a resiliently deformed condition.

Further features of this invention provide for the free ends of the loops to be bent away from each other and for the locking member to be a closed clip adapted to engage over the free ends of the loop and to be maintained in this position by the bent portions of the ends of the loops.

The invention also provides for the chain to be protective chain in which case the links are of wear resistant material, for the wear resistant links to be rectangular metal plates, for the apertures through the thickness of the plates to be nearer one longitudinal edge than the other and for the plates to be bent to give a crown effect to the wearing edge.

A preferred embodiment of the invention as applied to tire protective chain will now be described by way of example, reference being made to the accompanying drawings in which:

FIG. 1 is a plan view of a portion of a protective chain made according to the invention;

FIG. 2 is an isometric view of one connecting link operatively connected to four plate type links;

FIG. 3 is a sectional view taken along line A-A in FIG. 1; and

FIG. 4 is an elevation of an alternative form of platetype link.

The chain can be made to a variety of different patterns but the description will be limited to that shown with four separate links connected by a single loop. In general with my tire protective chain each loop must pass through an aperture in at least three separate links.

As shown in FIGS. 1 and 2 the wear resistant links 1 are made from suitable steel plate which is used edge on, these links 1 being of rectangular shape and approximately 100 mms long and 50 mms wide, for example. The plate links may, if desired, be bent along the long edge 3 so that a crowned effect is obtained in the middle of the link 1 as shown in FIG. 4. This enables more wear and a more positive grip to be obtained, since the link will wear at least down to dotted line 4 before failure is likelyto occur. In either case (i.e., whether these links are bent or not) they are provided with holes 5 made adjacent the inner edge 6 (i.e., the edge which is to contact a tire in use) so that connecting loops or connectors 7 can be threaded therethrough, this positioning of the holes providing for the maximum amount of wear of the links before failure.

These holes could, of course, be replaced by a single slot in the links.

Each connecting loop 7 is formed from a resilient steel rod as an open-ended rounded loop e.g. of omegashaped with the ends 8 bent outwardly to form notches A clip or the like member 10 is provided for each loop 7 so that once the required number of links have been threaded onto the loop the latter may be crimped with a suitable tool which may, for example, be a pair of bolt cutters with the jaws modified to grip the outer part of the loop 7. With the loop crimped the clip 10 may be slipped over ends 8 of the loop 7 to bridge the gap in the loop 7 and the tool then released. Preferably the clip 10 comprises an elongated metal plate having a slot 11 therein, the ends of the slot being, in the operative position, located in the recesses 9 of the loop. As shown, each clip 10 is arcuate and is located with its convexity towards the cavity of a loop 7 .to provide a projection into the gap formed by the ends 8 of a loop.

The inherent resilience of the material causes the loop to engage the clip 10 in recesses 9 and securely close the loop to prevent the links from coming apart. If desired, the clips can be permanently deformed to give complete locking engagement with the loop. It will be understood that strong engagement of the clip in the recesses is not required provided no possibility exists for the clip to come ofi during use of the chain.

The links 1 and connectors 7 from which the links 1 radiate form a reticulation of links and connectors.

It will be appreciated that the construction gives a protective chain affording a large wear resistant surface, which can be easily repaired as and when neessary and which may be manufactured less expensively than prior chains owing to the avoidance of welding operatrons.

It will also be understood that the invention can be applied to linear chains such as conveyor chains and the like.

What I claim as new and desire to secure by Letters Patent is:

l. A protective chain for a vehicle tire, comprising: a series of substantially omega-shaped loops each defining a cavity and having a pair of ends; groups oflinks threaded onto and radiating from and interconnecting said loops to form a reticulation of links and connectors; and a member bridging the gap in each loop and embracing said legs of each loop, each bridging member being arcuate and located with a convexity towards the cavity of a respective one of said loops.

2. A protective chain as claimed in claim 1 in which the ends of each loop are bent away from each other.

3. A protective chain as claimed in claim 2 in which each member is in the form of a closed clip.

4. A protective chain as claimed in claim 3 in which each clip is in the form of a metal plate having a slot therethrough.

5. A protective chain as claimed in claim 2 in which each member is maintained in the operative position by means of the bent ends of the loop with which it is associated.

6. A protective chain as claimed in claim 1 in which the links are in the form of metal plates.

7. A protective chain as claimed in claim 6 in which each loop passes through a separate hole in a plate.

8. A protective chain as claimed in claim 1 wherein each loop passes through apertures in at least three different links and said links are made of wear resistant material.

9. A protective chain as claimed in claim 8 in which the apertures in said links are offset to one side of the center line thereof. 

1. A protective chain for a vehicle tire, comprising: a series of substantially omega-shaped loops each defining a cavity and having a pair of ends; groups of links threaded onto and radiating from and interconnecting said loops to form a reticulation of links and connectors; and a member bridging the gap in each loop and embracing said legs of each loop, each bridging member being arcuate and located with a convexity towards the cavity of a respective one of said loops.
 2. A protective chain as claimed in claim 1 in which the ends of each loop are bent away from each other.
 3. A protective chain as claimed in claim 2 in which each member is in the form of a closed clip.
 4. A protective chain as claimed in claim 3 in which each clip is in the form of a metal plate having a slot therethrough.
 5. A protective chain as claimed in claim 2 in which each member is maintained in the operative position by means of the bent ends of the loop with which it is associated.
 6. A protective chain as claimed in claim 1 in which the links are in the form of metal plates.
 7. A protective chain as claimed in claim 6 in which each loop passes through a separate hole in a plate.
 8. A protective chain as claimed in claim 1 wherein each loop passes through apertures in at least three different links and said links are made of wear resistant material.
 9. A protective chain as claimed in claim 8 in which the apertures in said links are offset to one side of the center line thereof. 